This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Mucosal transmission is the principal route of HIV infection. It has been shown that the mucosal early innate interferon response plays an important role against HIV infection. However, the mucosal immune response against HIV would be more effective if the neutralizing secretory immunoglobulins A and G response could be enhanced. It has been reported that highly exposed, persistently seronegative patients such as Gambian sex workers, and partners of HIV infected persons who have unprotected sexual relations exhibit higher Gag, Pol and Nef-specific T cell IFN-gamma responses in cervical mucosa, as compared to HIV-seropositive patients. Moreover, several groups have shown that Gag induces an HIV-specific T-cell and IgA immune responses at mucosal sites of lung and vaginal tract, besides that Gag, Nef, and Pol have been used in numerous mucosal immunization protocols. Therefore, the selection of Gag, Nef and Pol as antigens in combination with a mucosal immunization approach is expected to have a positive impact in the HIV-specific immune responses. DNA based vaccines are known to elicit both: cell- and humoral-mediated immune responses, however there is a need to increase the amplitude of their response in humans. On this project, we will determine the immunomodulatory effect of Imiquimod (a Toll-like receptor 7 agonist) in the enhancement of the HIV-specific immune response on a DNA vaccination platform, after vaccination of C57BL/6 mice. Cell- and humoral-mediated immune responses, as measured by ELISPOT and ICC analysis in these mice, will be correlated with control of viremia after qPCR analysis of serum from recombinant HIV-vaccinia infected mice. We hypothesize that Imiquimod, will enhance the HIV-gag, nef and pol specific mediated immune responses, after a DNA based mucosal immunization in mice. We therefore expect that these results could be moved easily and safely into the clinics, and therefore, could be tested in humans.